Hydraulic valve



June 9, 1925. 1,540,962

, G. JFSTUARJT HYDRAULIC VALVE Filed Feb. 10. 1923 Shee os Sheet 1 ATTOkNEY June 9, 1925.

Filed Feb. 10. 1923 s Shets-Sheefi 2 IN V EN TOR.

7304M ATTORNEY G. J. STUART HYDRAULIC VALVE Filed Feb. 10.

June 9, 19251 1923 3 Sheets Sheet 3 INVENTOR. .W*

ATTORNEY.

Patented June 9, 1925. i

,- UNITED STATES HYDRAULIC vALvn. r

Application filed February 10, 1923. Serial No. 618,326.

To all whom it may concern:

Be it known that I, GEORGE J. ST ART, a citizen of the United States, residmg at Pittsburgh, in the county of Allegheny and,

State of Pennsylvania, have invented new and useful Improvements in Hydraulic Valves,of which the following is a specification.

My invention relates to hydraulic valves for controlling the flow through them of fluids having different pressures.

, This invention embodies improvements on the hydraulic valves shown in my Patent No. 1,192,472, granted July 25, 1916, and in my application Serial No; 448,571, filed February 28, 1921, and its object is to simplify the parts and rearrange some of them whereby the operating cost is lowered and the efliciency is bettered.

Referring to the accompanying drawings, Fig. 1 is a central longitudinal section through a hydraulic valve containing my improvements; Fig. 2, a central longitudinal section on the line IL-Il of Fig. 1, parts being in elevation;.Fig. 3, a section similar to Fig. 2, but with the moving parts all shown in elevation; Fig. 4, a side elevation showing my invention, parts being broken off; Fig. 5,across-section on the line VV.

of Fig. 1; Fig. 6, a section on. the line VIVI of Fig. 1; and Fig. 7, a perspective view of the sleeve or bushing for thehighpressure valve.

On the drawings, 1 designates the casing 3 having the central main member 2, and the two lateral members 3 and 4, integral therewith and connected to the main member 2 by the necks 5 and 6 respectively.

The main casing member 2 has a vertical longitudinal opening having its lower cylindrical portion or 7 section 7 closed at the lower end, the closure 8 containing the removable screw-plug 9. Above the section 7, the said opening is enlarged to form the chamber or-section 1O limited at its upper end by the internal flange or seat 11. The said opening is continued above the seat well into the upper endof the main casing member 1. A cap 12 is screwed into the upper end of the said opening and has integral therewith the sleeve or bushing 13 extending down through the seat 11 which it fits. The .bushing 13 has an annular groove or channel in which an annular packing ring 13 is seated and which bears against the seat 11. 14 is an annular passage above the seat 11 and in the casing member 2v andthe b ushing bythe ports 13, the passage being connected 15 to the chamber 16 within the b'ushing. The lower end ofthis chamber has the circular internal flange or valve-seat 17 in axial alinement with the section 7. 18 is the exhaust port leading from the chamber 14. A pipe connects the port 40 to the press 61 having the working plunger 62 acted on by the fluid passing through the pipe 60 to raise the press table 63 and compress the articles 64 between itself and the top or cover of the press.

The casing member 3 has .thechamber 19 communicating with the annular passage 20 in the casing member' 2 intermediate the ends of the section 7 of the said central opening, the chamber 19 being connected to the section 7 by the ports 21. The lower side of the casing member 3 has the lowpressure inlet 22. A check-valve 23 permits fluid to pass from the inlet to the chamber 19, but prevents its flow in the contrary di- -rection. The chamber is' closed by the screw-cap 24 in axial aline ment with the Gil check-valve and has the axial hole 25 to receive the stem 26 on the top of the checkvalve for guiding the latter.

The casing member 4 is shown diametrically opposite to the member 3, having a removable cap-portion 27 provided with the port 28. Within the member 4 is the chamber 29 containing the horizontal piston 30 with the two piston members 31 and 32, the latter preferably having the smaller area which faces the port 28. There is an opening between the passage 20 and the chamber 29, this opening containing the sleeve 01' liner 33 held in place by the screw-ring 34 1? bearing on an. external flange projecting into a channel in the metal of the member 4. The neck 6 has the annular passage36 open to the 'ports'37'in the sleeve 33. The sleeve 33 which extends from the chamber 29 to the passage 20 has the cylindrical high-pressure valve 38 connected rigidly to the piston 30. The former has two packing rings 39 between which the circle of ports 37 are when the piston is in its innermost position, as shown Fig. 1. Travel of the valve-member and .1ts length are suchthat, when the valve 30 moves to its extreme outer position,-as shown in Fig. 5, the inner end of the valve uncovers the ports 37, that is, opens'a'passage from the chamber 36 to the passage 20. The neck 6 has the high-pressure inlet port 40 42 is reduced between the heads 43 and 44 so as to provide the annular chamber or passage 48. The upper end ofthe stem 42 has the cylindrical valve 49 fittm and slidable in the circular seat 17, a pac ingring 50, like the packing rings 39 and 46 being seatedin the inner face of the sleeve 13 and bearing on the adjacentface ofthe valve 49.

An actuating rod 51 is screwed into the upper end of the stem 42 and extends up through the cap 12. It is operated by the manually-operated lever 52, pivoted to the upper end of the link 53 pivotally supported by the casing member 2, the lever being pivoted to the fitting 54 secured to the top of the rod 51.

The distance between the heads 43:and 44, and betweenthe head 44 and the valve 49, and the length of the section 7 and of valve 49 are such that thehead 44 is always in the section 7 and that they accomplish the following: lVhen the stem 42 is in the neutral position, as shown in Fig. 1, and in full lines in Fig. 2, the head 44 is entirely above the ports 21, and the head 43 is below said ports, as it always is, and the stem is in a balanced condition, and the valve 49 is on its seat 17. When the stem is in the position shown in dotted lines in Fig. 2, the head 44 has descended so as to open communication directly between the ports 21 and that part of the section 7 above the head 44; the ports 21 remain open to the chamber'48 to maintain the stem in a balanced condition; the valve 49 is still on its seat 17 \Vhen the stem is raised above its neutral position to that shown in Fig. 3, the ports 21 are still 0 n to the chamber 48, but not to the s ace a ove the head 44; and the valve 49 is a ove the seat 17 so as to directly connect the chambers 10 and 16.

In order to permit the stem 42 to descend without opposition by water escaping ast the head 43, the fluid may be drained 0 by removing the plug 9, ,but I prefer to accomplish the same result by making the stem with the longitudinal opening 55 which communicates with the chamber 16 by means of the ports 56 in the upper end of the stem.

Low-pressure fluid is supplied to themeing member 3 by the pipe 57,. which also has the pipe connection 58 leading to the port 28 in the casing member 4. The pipe 59 conveys high-pressure.fluid to the port 40 in the casing member 2. The pipe 60 connects the port 40' to the hydraulic press 61 or similar device.

The operation of my invention is as follows: T e parts being asin Fig. 1 and in full lines in Fi 2, the low-pressure fluid from the pipe 5 occupies the chambers 19, 20 and 48, but has no access to the chambers 10 and 36. The high-pressure fluid from the pipe 59 occu ies t e chamber 36 but cannot esca e into t e chamber 20 because the valve 38c oses the orts 37, the-piston 30 being moved to and held in its right hand position bythe low-pressure fluid in contact with the piston member 32. The pressure in the chamber 10 is low as it was open to the exhaust at the conclusion of a preceding operation.

The lever 52 is raised, moving the stem- 42 to its lowest position shown in' dotted lines in Fig. 2. The low-pressure fluid flows from the pi 57 throu h the inlet 22, past the check-Va ve 23, and t rough the chamber 19, the chamber 20, the ports 21 the section 7 above the head 44, the chamber 10, and the port 40 to the pipe 60. The piston 30 is held towards the right by the low-pressure fluid against the piston member 32 until the fluid flowing out is rough the pipe 60 encounters increased resistance in the press 61, suflicient to cause the ressure against the piston member 31 to build up to such a value as to force the piston 30 to its lefthand position, shown in Fig. 5. As soon as the piston 30 has taken its second or lefthand position, the high-pressure fluid from the pipe 59 passes through the assage 36, the ports 37, the inner end of the Bushing 33, the passage QO-and-the' ports 21 to the pipe 60 and ress 61' as before. The check-valve 23 is he (1 closed by the high-pressure fluid to prevent the latter entering the low-pressure'pipe The ap aratus, as a press 61, connected to the pipe will then receive its highest pressure.

\Vhen the handleis moved downwardly sufficiently, the stem 42 will have the position shown in Fig. 3. Here the head 44 is again above the ports 21, thereby cutting all fluid supply to the pipe 60. The valve 49 opens the chamber 10 to the exhaust chamber 16, allowing the fluid in the press to escape through the exhaust port 18. The reduced pressure onthe piston member 31 allows the pressure on the piston member 32 to close the valve 38. \Vhen' the exhaust operation has proceeded as far as desired, the lever is moved to its middle position, as shown on Figs. 1 and 4, when all fluid-flow is prevented until the. lever 52 has been operated again to initiate another cycle of operations like the one just described.

The several packing ring holders are provided with small passages 65 permitting the fluid to have access to the packing rings to make them tightly seal the joints which they are intended to seal.' These features will form the'subject matter ofa separate application.

By making the stem 42 in one piece I have greatly simplified the construction as compared with that shown in my said application. By providing the stem with an ex haust valve distinct from the heads 43 and 44, the-"exhaust is moredirectly and simply connected to the main pressure chamber 10 and tothe working face ofthe piston 30. By making the piston and the valve 38 at a right angle with the casing member 2' or the stem 42, and locatingthe valve 38 practically in line with the chamber 20 which is in direct line with the chamber 19, I simplify the courses of the fluid and the construction of the apparatus.

It is to be noted that my invention has two valves 38 and 44;, between the high-pressure chamber 36 and the chamber 10, and

that during the exhaust operation both these valves are closed as shown in Figs. 1 and 3. This has a decided advantage as each valve is an additional safeguard against leakage in case one of them permits leakaga I claim 1. In a, hydraulic valve, a casing having therein an exhaust chamber, a common re ceiving chamber for two fluid pressures,

, and a third chamber having a port for connection to a hydraulic press or the like; a stem reciprocable in the casing; a valve carried by the stem for opening and closing connection between the last two chambers; a head carried by the stem for balancing the pressure on' the said valve when closed; and a second valve carried by the stem for opening connection between the first and third chambers only after the first valve has been closed.

2. In a hydraulic valve, a casing having therein an exhaust chamber, a common receiving chamber-for two fluid pressures, and a third chamberhaving a port for connection to a hydraulic press or the like; a stem reciprocable in the casing; a valve carried by the stem for opening and closing connection between the last two chambers; a head carried by the stem for balancing the pressure on the said valve when closed; a second .valve carried by the stem for opening connection between the first and third chambers only after the first valve has been closed; and means for automatically admitting the higher pressure to the common chamber only after resistance to the lower pressure reaches a certain value.

3. In a hydraulic valve, a casing having therein an exhaust chamber, a common receiving chamber for two fluid pressures, and

a third chamber having a port for connection to. a hydraulic press or the like; a stem reciprocable in the casing; a valve carried by the stem for opemng and closing connection between the last two chambers; a

head carried by the stemfor balancing the pressure on the said valve when closed; and a second valve carried by the stem for opening connection between the first and third chambers only after the first valve has been closed, the stem being compose-d of one piece, and the first valve and the head being integral therewith and having peripheral grooves containing packing rings.

4. In a hydraulic valve, a casing, a common chamber to receive two pressures, an opening in the casing having ported connection with the common chamber, a balanced piston in the opening having packed heads on opposite sides of the ports, a second chamber in the casing connected to the first chamber by the said opening, one of the heads acting as a valve to admit the pressure from the first chamber to the second chamber, means permittingthe higher pressure to enter the first chamber only when the pressure in the latter chamber reachesa predetermined value, an exhaust valve for the second chamber, capable of being opened only when the first valve is closed.

5. In a hydraulic valve, a main casing member having therein an exhaust chamber, a common receiving chamber for two fluid pressures, anda third chamber having a port for connection to a hypraulic press or the like; a stem reciprocable in the casing;'a valve carried by the'stem for opening and closing connection between the last two chambers; a head carried by the stem. for balancing the pressure on the said valve when closed; a second valve carried by the stem for opening connection between the first and third chambers only after the first valve has been closed; a second casing member connected to the main casing member, a high-pressure receiving-chamber in the second member, a passage between the latter chamber and the common chamber and having one end opening into the latter chamber, a valve in the passage for permitting the higher pressure to flow through the passage into the common chan iber.

6. In a hydraulic valve, a source of high pressure, a source of lower pressure, a common chamber to receive the pressures, a valve controlled by the low pressure for admitting the high pressure to the commonchamber and cutting it OK therefrom, an exhaust chamber, and a third chamber having a port for connection to a hydraulic press or the like, a valve to open and close connections between the common chamber and the third chamber, and an exhaust valve between the third chamber and the exhaustchamber adapted'to be open only when the first two valves-are closed.

7. In a valve, a casing, a chamber therein,

higher pressure to the said chamber, the second means being operated b the first-named fluid when it reaches a pre etermined value and an exhaust passage connectible to the chamber, but only after the first means cuts off from the chamber the fluid under both the higher and the lower pressures.

8. In combination, a casing, a chamber therein, means for admitting a fluid under pressure to the chamben means for causing the pressure in the chamber to be temporarily below the normal pressure of the said fluid, means controlled by the said fluid in the chamber, when the pressure thereof is built up to a predetermined value, for admitting to the chamber a fluid having a ressure higher than that of the first-named uid and an exhaust passage connectible to the chamber, but only after the first means cuts off from the chamber the fluid under both the higher and the lower pressures.

9. In a. valve, a casing, a chamber therein, means for admitting a fluid .under pressure to the chamber, means for admitting a fluid under a higher pressure to the chamber, the

second means being operable automaticallyby the pressure in the chamber 'when the pressure reaches a predetermined value, and an exhaust passage, the first means being adapted to arrest the flow to the chamber of the fluid under both pressures without opening the exhaust passage.

In testimony whereof I hereunto afiix my signature this 22nd dayof January, 1923.

GEORGE J. STUART. 

